I posted Re: opening the cd rom yesterday, but now I have a question myself. I copied the original code here, so it is easy to reference. It was a piece of code to eject CDROM:

use Win32::API;

use strict;
use warnings;

my $f = Win32::API->new("winmm", "mciSendString", "PPNN", "N");
my $ret = ' ' x 127;  
my $return = $f->Call('set CDAudio door open', $ret, 127, 0);

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I came from c background, so I tried to modify the API interface to c style, which makes much more sense to me: 

use Win32::API;

use strict;
use warnings;

my $f = Win32::API->new("winmm", "long mciSendString(char * a, char * 
+b, long c, long d)");
my $ret = ' ' x 127;  
my $return = $f->Call('set CDAudio door open', $ret, 127, 0);

[download]

This didn't work, and core dump. I tried couple of other variances, but none of them worked. Please help.

Update:

Changed the code to something like this:

use Win32::API;

use strict;
use warnings;

my $f = Win32::API->new("winmm", 'long mciSendString(LPSTR a, LPSTR b,
+ long c, long d)');
my $ret = ' ' x 127;
$f->Call('set CDAudio door open', $ret, 127, 0);

[download]

Now it gives this error:

Modification of a read-only value attempted at C:/Perl/site/lib/Win32/
+API/Type.p
m line 195, <DATA> line 164.

[download]

In reply to c style Win32::API interface by pg

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